1. Field of the Invention
This invention relates generally to dispensing closures for containers, and more particularly, to such closures in which a universal base is usable interchangeably with either a twist cap or a pull/push cap to complete the closure.
2. Description of the Prior Art
Twist top or pull/push closures are known in which a cap with a central aperture cooperates with an upstanding post formed on a base to open or close the closure. The base is affixed to the mouth of a product container, such as a water bottle, and when the cap is moved, such as by twisting or pulling relative to the base, the post on the base is withdrawn from engagement with the aperture in the cap to permit product, such as water, in the container to be dispenses by passing through the aperture. After dispensing of the product is completed, the cap is returned to its closed position by reverse-twisting or pushing on the cap to re-engage the post in the aperture and thereby close the closure and prevent product from being dispensed from the container.
Examples of twist top and pull/push closures of the type referred to above are shown in the following U.S. patents which are owned by the same assignee as the assignee of the present application: U.S. Pat. No. 5,328,063 issued Jul. 12, 1994 entitled "Venting Closure Cap"; U.S. Pat. No. 5,967,941 issued Nov. 6, 1990 entitled "Twist Lock Adjustable Metering Closure Cap." The disclosures of said two patents which illustrate structure and operational features of examples of twist top and pull/push closures hereby are incorporated herein by reference.
The disclosure of U.S. Pat. No. 5,328,063 shows a pull/push closure in which a cap is mounted on its associated base and the closure is opened/closed by assertion of a pull/push force upon the cap with respect to the base. The disclosure of U.S. Pat. No. 4,967,941 shows a twist type closure in which the cap rides on a ramp formed in the associated base when the cap is twisted with respect to the base of effect the open/close operation of the cap with respect to the base.
In order to facilitate the different types of open/close operations of pull/push-twist closures, the respective bases of the '063 and '941 patents are formed with different constructional elements. In an effort to eliminate the requirement to produce base parts having such different constructional elements, it is desirable to provide a single universal base that can be used interchangeably with either a twist operation cap or a cap which is operational by asserting a pull/push force. Such single universal base construction will afford the advantage of saving the cost of having two different types of bases available for use with a desired twist or pull/pus operational cap.